Tridimensional radio navigational system



y ,1946. G. G. GAGE 2,399,671

TRI-DIMENSIONAL RADIO NAVIGATIONAL SYSTEM 5 Filed April so, 1943 18 Sheets-Sheet 1 mm pw'gq l-x s'rA'rzMS men-map Q DvGG-aeut-v Wsmo we: X} G a w w W IN V EN TOR. 0 WARD 0. 6/: as

A T7'ORNEX May 7, 1946. E. G. GAGE 2,399,671

TRI-DIMENSIONAL RADIO NAVIGATIONAL SYSTEM Filed April 30, 1943 18 Sheets$heet 2 135 r 135 do/57:9. 15 163 RECEIVER INVENTR.

EDM/ARO 6161405 BY V I ATTORNEY y 7, 1946. E. G. GAGE 2,399,671

TRI-DIMENSIONAL RADIO NAVIGATIONAL SYSTEM Filed April 30, 1943 18 Sheets-Sheet 3 i 50.9 H 204/ H r 20 ii .204 Q- 5 .9 w

802' :5 Z01 i I Q I 808 1' H m \W u 510 I i 6mm; 6mm TOR 200 I & H z1z I o VU Q h- 0 50a 212 216 214 806 l RECEI YER Ascs/vse 2 65 10111005 EQUALITY 66.9 RAY TESTER Tues INVENTOR. [AWARD 6. 6A 65 A TTORA/EX May 7, 1946. E. G. GAGE TRI-DIMENSIONAL RADIO NAVIGATIONAL SYSTEM Filed April 30, 1943 18 Sheets-Sheet 4 IN VHV TOR. Eownw 66/16::

A T Tomi/5).

y 7, 1946. E. G. GAGE 2,399,671

TRI-DIMENSIONAL RADIO NAVIGATIONAL SYSTEM Filed April 30, 1943 18 Sheets-Sheet 5 Q W ses 251- INVENTOR.

EDWARD 6. 6465 BY 5 a z A TTOR/VEX May 7, 1946. E. G. GAGE TRI-DIMENSIONAL RADIO NAVIGAT IONAL SYSTEM Filed April 30, 1943 18 Sheets-$heet 6 QN S Ink

INVEN TOR. fDW/IRD G 6A6:

May 7, 1946. E. G. GAGE 2,399,671

TRIDIMENSIONAL RADIO NAVIGATIONAL SYSTEM Filed April 30, 1943 18 Sheets-Sheet 7 1 348 T TELEV/S/OM/ TRANSMITTER 330 b 1 Mom 75 Haw TELEV/J/ON Com/4:5 V E Z /vR 54514510 TRANSMITTER IN V EN TOR [ow/mo 6.6405

BY Z

ATTORNEX May 7, 1946. E. G. GAGE TRI-DIMENSIONAL RADIO NAVIGATIONAL SYSTEM Filed April 30, 1943 18 Sheets-Sheet 8 INVENTOR. [DWARDG GAGE A T TOR/V5)? May 7, 1946. s G. GAGE TRI-DIMENSIONAL RADIO NAVIGATIONAL SYSTEM Filed April 30, 1943 18 Sheets-Sheet 9 IN VEN TOR EDWARD G GA 0:

A TTORA/EX May 7, 1946. E. G. GAGE 2,399,671

TRI-DIMENSIONAL RAljIO NAVIGATIONAL SYSTEM Filed April 50, 1943. 1a Sheets-Sheet 10 INVEN TOR. f 0 WA RD 6 6AG A rronmsx- May 7, 1946. E. G. GAGE TRI-DIMENSIONAL RADIO NAVIGATIONAL SYSTEM Filed April 30, 1943 18 Sheets-Sheet 11 IN VEN TOR. fowA/w GGAcg A T TOR/V5 X May 7, 1946. E. G. GAGE TRI-DIMENSIONAL RADIO NAVIGATIONAL SYSTEM Filed April 30, 1945 18 Sheets-Sheet 13 IN V EN TOR. 0 WARD 6. GA 6E A T TORNE Y May 7, E. G. GAGE TRI-DIMENSIONAL RADIO NAVIGATIONAL SYSTEM Filed April 30, 1943 18 Sheets-Sheet 14 a INVENTOR.

EDWARD GIG/1c:

ATTORNEY: v

May 1946. E. G. GAGE 2,399,671

TRI-DIMENSIONAL RADIO NAVIGATIONAL SYSTEM Filed April 30, 1943 18 Sheets-Sheet 15 587 ,593 592 i RECEIVER g 9 L c E 3 Rae/va IN V EN TOR. E 0 WARD @6465 A 7 TORNEY y 7, 1946. E. G. GAGE 2,399,671

TRI-DIMENSIONAL RADIO NAVIGATIONAL SYSTEM Filed April 50, 1943 18 Sheets-Sheet 16 T w I w 9 l 1 RECE/V'k 702 i =1: 1- 702 67.9 j

JIGNAL GENERATOR A 7 1K 667 666 V w RECEIVE? 1 INVEN TOR. fowzwo 6. 6A 66 A T TORNE X y 1946- E. G. GAGE 2,399,671

TRIDIMENSIONAL RADIO NAVIGATIONAL SYSTEM Filed April 30, 1943 18 Sheets-Sheet 17 7 008 00.9 .96 0 7.47 I i 80 001 I 05 11 q 01 606 IN VEN TOR. [ow/4R0 6. GAGE May 7, 1946.

E. G. GAGE TRI-DIMENSIONAL RADIO NAVIGATIONAL SYSTEM- Filed April 50, 1943 18 Sheets-Sheet 18 mdas 553 651 E 15 557 "859' INVEN TOR. 0WAR0 6.640:

A TTORNEK Patented May 7, 1946 2,399,671 TRIDIMENSIONAIYRADIO NAVIGATIONAL STEM Edward G. Gage, Brooklyn, N. Y., assignor of twothirds to Leon Ottinger, New York, N. Y.

Application April 30, 1943, Serial No. 485,113

48 Claims.

The invention relates to systems for locating a source of electromagnetic waves, more especially adapted for the determination of the distance between two points and direction with relation of one of the points to the other, either of which points may be movable with respect to the other. The system is particularly designed for the location of a fast-moving vehicle or craft such as, for example, a high-speed airplane or high-speed motor boat, visual means being provided whereby instantaneous observations may be made.

In a prior Patent #2,255,659, I have disclosed an arrangement of transmitting and receiving apparatus which requires a minimum number of transmitters, the same being used in groups to radiate at all times a substantially 360 circular pattern from a predetermined location. This will permit a moving vehicle, such as an airplane, to be guided to the center of the landing field bounded by the said transmitters from substantially any direction and it will afford means for measuring the distance of the moving vehicle in any direction from the transmitter system.

The present invention involves a system which is of a nature somewhat reverse in its operation of the aforesaid patented system. T l. l1.l hl 1 fi Ellefigl i lLfi imjutilized. wh the m i itgs or tnepate iejrsha iaierenl ces by direction-finding receiver units similarly located'ili predetermined pattern ,withirry hlclg is located th e point of obs erv ation, preferably Fi L QiJhEfiftfihifindm units or in .ias smryr i ected one eitheseunits.

I rov is ion is maile'for transmitting to a visual indicator located at the observation point the respective effects of the energy received by the several direction-finding units, these effects being juxtaposed in a novel manner atthe visual i ndicgf rffki exafnplfupoh the screen of one or seyemhcathodelayji bgg, aiidwith respect to one another and to a scale or scales associated therewith.

The novel system may be considered to be based upon the following theorem:

If the diameter of a circle forms the base of an isosceles triangle, and the vertex is a point outside the circle, the angle formed by the two arms will be indicative of the distance from the vertex to the center of the circle.

The requirements necessary to reduce this theorem to practice would be too severe, as an infinitely large number of radio direction-finding stations would be necessary, distributed on the circumference of a circle. Accordingly, a more suitable variation of the theorem is involved in the practical embodiment which reduces the number of radio direction-finding stations necessary.

In a more practical form the theorem may be expressed as follows:

If the diagonal of a regular polygon having an even number of sides forms the base of an isosceles triangle, the vertex of which is outside the polygon, the angle formed by the two arms of the triangle will be indicative of the distance from its vertex to the center of the polygon.

The system then operates practically on the above theorem in the following manner. An airport, for example, is designed in the form of a regular polygon having an even number of sides such as a hexagon, as in the system hereinafter described. Such a figure has six possible diagonals.

A radio direction-finding station may be located at each of the six vertices of the regular polygon so formed. A moving craft, such as an airplane equipped with a radio transmitter, represents then the vertex of an isosceles triangle, located outside the polygon and approximately in the same azimuthal plane.

Two of the six direction-finding stations located at diametrically opposite vertices of the polygon (airport) 81td fls the point of intersection of the Base and'arms of the isosceles triangle, the base being the diagonal. This diagonal will be the one which is nearest at right angles to a line drawn from the vertex of the isosceles triangle to the center of the polygon, since this is the only diagonal which will form the base of an isosceles triangle. All the others form sides of unequal angles.

If a line is drawn from the craft intersecting one vertex of the polygon, or radio directionfinding station, and another line from the craft intersects a diametrically opposite vertex of the polygon, or another radio direction-finding station, it will be found that an isosceles triangle has been formed, the base of which is the diagonal of the polygon, the vertex is the craft outside, and the two arms are the lines joining the vertex with the base.

The two arms represent hypothetical lines formed by the path of radio reception from the craft to the direction-finding stations, and the reception width of this path or line is indicative of the direction discrimination of the directionfinding means.

The degree of angle at the vertex of the isos celes triangle represents the distance of the craft from the center of the airport, and this angle will always be formed when the craft is at this distance from the center of the airport.

In practice, a polygon is selected which will best suit the conditions under which the system is to operate. In general, the greater the number of sides, the greater will be the accuracy of the measurements taken.

A regular polygon having an odd number of sides or vertices may be used to define the location of the direction-finding stations, but if this form is selected, the distance-measurements will not be from a point in the center of the polygon, but from a point on the polygon diagonal or base of the isosceles triangle. It is not necessary to form the base of the isosceles triangle from the diagonal of the polygon. It may be formed from one of the sides, but in this instance also the distance is measured from the vertex of the isosceles triangle to a point on the side of the polygon, although, by calibration, this point may be shifted to the center of the polygon by projecting a median from the vertex of the isosceles triangle to a point in the center of the polygon, and suitable correction made on the calibrated scale.

It is obvious that when any figure except a circle is used to define the direction-finding station locations, there must be sacrifices made as to accuracy, and in the interest of practical economy. One of the best polygonal figures is found to be a hexagon because alternate vertices of the figure may be omitted, leaving a triangle, and still maintain the desired omni-directional reception features. This is possible because every direction from center is duplicated at 180, and if the 180 ambiguity can be eliminated, then half the number of vertices on a polygon may be omitted.

In its simplest embodiment, the novel system comprises three stations or direction-finding receiving units located as hereinbefore set forth with a single transmitter station on the craft remote from these stations, and is designed for measuring in azimuth only. However, by constructing the transmitter with a horizontally and .Lmicalmmlariaechtransmittms.

tem and associating with the respective directionfinding receiving units additional antennae correspondi y polarized. cmminati nslnzcnitn or altitudinal measurement may also be ma it it beingiinderstood, of course, that'the respective determinations are transmitted at difierent frequencies to juxtaposed positions on one or more visual indicator means.

It is to be understood, also, that the transmitter may be located at a stationary point and the group of respective direction-finding receiver units on a mobile vehicle. The visual indicator means utilized in connection with the novel tri dimensional navigational system described herein requires simultaneous viewing of all directionfinding indicators in juxtaposed relation to one another and to a suitably calibrated scale.

A preferred form of receiving indicator is the cathode ray screen actuated from two directionfiinding systems, such as crossed loops or crossed Adcock antennae, according to the general scheme of the original Watson-Watts cathode ray compass. Meters may also be used but are not adaptable to rapid switching, that is, they cannot be instantly switched from one set of receivers to another without fluctuation Of t meter needles.

fix

distance from a given point of, a transmitter gf electromagnetic waves, remote from the point of observation, either of which may be stationary or movable.

The invention has for an object, also, to provide for a novel system wherein measurements in azimuth as well as altitudinal measurements may be efiected instantaneously, that is to say, by viewing characteristic indicia on a screen.

Another object of the invention is to provide means whereby it becomes possible to determine from an inspection of a visual indication the particular geographical sector over which the direction-finding signal energy is being received by a plurality of direction-finding units fixedly located relatively to each other and to the location of the point of measurement.

Still another object of the invention is to provide suitable indicia corresponding to respective direction-finding receiver unit locations, said indicia, straight-line images upo n ma n Still another object is to provide straightdine images upon the screen of a cathode ray tube indicative of the respective direction-finding receiver unit locations, whighimaggadiverge from the center of the said screen in one quadrant only and the two outermost serve as a measure of distance of the remote transmitter and the one nearest the middle serves to determinethe geographical secton'over which the. transmitter is operated as well as its direction.

Still another object of the invention is to provide in connection with the direction-finding units a pair of receiver members with translation or amplifier means, together with means for equalizing respective amplification gain of each of the translation means by comparing their efiects simultaneously upon a single screen of a cathode ray tube.

A further object is to televisg, to the screen of a cathode ray tube respective indicia from direction-finding units when these indicia are of a character to require pictorial representation.

The invention has for an object, also, to pr0- vide modulating means for the transmitted or received energy, said means being in the nature of a pulse generator.

A further object of the invention is to associate several visual indicator means receiving respectively the energy eifects from difierently located direction-finding units.

A still further object is to provide a double viewing cathode ray screen for simultaneous viewing of two images; also, to provide for the association of a group of cathode ray screens in close proximity such as a means for afiording simultaneous viewing of the images of each cathode ray tube.

Still another object is to provide indicia on the screen of cathode ray tubes particularly indicative of dimensions to be measured.

The invention has for an object, also, to provide a rotary switch for connecting sequentially for example, being constituted as 

